8.1.1 Disable VM communication through VMCI

Information

Configure the Virtual Machine Communication Interface (VMCI) to restrict VM
communication.

*Rationale*

If the interface is not restricted, a VM can detect and be detected by all other VMs with the
same option enabled within the same host. This might be the intended behavior, but
custom-built software can have unexpected vulnerabilities that might potentially lead to an
exploit. Additionally, it is possible for a VM to detect how many other VMs are within the
same ESXI system by simply registering the VM. This information might also be used for a
potentially malicious objective. By default, the setting is FALSE. The VM can be exposed to
other VMs within the same system as long as there is at least one program connected to the
VMCI socket interface.Guest-to-guest communications (virtual machine to virtual machine) are deprecated in the
vSphere 5.1 release. This functionality will be removed in the next major release. VMware
will continue support for host to guest communications.

Solution

To implement the recommended configuration state, run the following PowerCLI
command-
# Add the setting to all VMs
Get-VM | New-AdvancedSetting -Name 'vmci0.unrestricted' -value $false

Impact-Virtual machines will be unable to communicate using VMCI technology.

Default Value-The prescribed state is the default state.

See Also

https://workbench.cisecurity.org/files/902

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(21)

Plugin: VMware

Control ID: 99ea5a79b26afeb91fafc940b4fafc1d93317df28947e42e3decf13833f366e3